On Fri, Oct 21, 2022 at 09:58:57AM +0800, Jianmin Lv wrote: > On 2022/10/21 上午12:47, Bjorn Helgaas wrote: > > On Thu, Oct 20, 2022 at 04:22:02PM +0800, Jianmin Lv wrote: > > > On LoongArch ACPI based systems, the PCI devices (e.g. sata > > > controlers and PCI-to-to PCI bridge controlers) existed in > > > Loongson chipsets output high-level interrupt signal to the > > > interrupt controller they connected to, > > The point is that one should be able to write this code from a spec, > > without having to empirically discover the interrupt polarity. What > > spec tells you about using ACTIVE_HIGH here? > > > Yes, no mentions for the inverter in ACPI spec, the description about > device interrupt type can be found in Loongson chipset manual: > > https://github.com/loongson/LoongArch-Documentation/blob/main/docs/Loongson-7A1000-usermanual-EN/interrupt-controller/device-interrupt-types.adoc That's the kind of reference I was looking for. The link to HTML is convenient in some ways, but since specs evolve over time and URLs are ephemeral, I think a citation like "Loongson 7A1000 Bridge User Manual v2.00, sec 5.3" is more likely to be useful far in the future. Bjorn
